1. Field
One embodiment of the invention relates to a luminance signal color carriage signal separating circuit (hereinafter simply referred to as a YC separating circuit) and method, the circuit being improved so as to have the enhanced ability to eliminate dot interference.
2. Description of the Related Art
Various YC separating circuits have been proposed (for example, Jpn. Pat. Appln. KOKAI Publication No. 2006-25098). The YC separating circuit separates a luminance signal (hereinafter referred to as a “Y signal”) and a color carriage signal (hereinafter referred to as a “C signal”) from a composite video signal (composite signal).
A YC separating method utilizes the inversion of the C signal at each horizontal period. This method determines the difference between horizontal lines to extract the C signal and then subtracts the extracted C signal from the composite signal to obtain the Y signal. Dot interference is likely to occur in this calculating process if the C signal is mixed into or remains in the Y signal. The dot interference is a phenomenon in which smaller dots appear in a part of the video corresponding to a part of the signal which contains discontinuous colors.